1. Field of the Invention
The invention relates to a method of processing sewage, as distinguished from "treating" sewage. "Treating" sewage generally entails adding chemicals to the sewage. During treatment, chemicals generally neutralize the effluent to return to the environment as the waterways and atmosphere and the like. Processing sewage in accordance with the invention entails vaporizing the vaporizable components of the sewage while disintegrating the solid components via a freeze-drying process or a combination centrifugal separation and evacuated "bake-out" process, and so on.
2. Prior Art
The popular method for handling sewage in sewage plants entails "treating" the sewage with relatively expensive chemicals. There are several shortcomings associated with treating sewage via chemicals. The chemicals that are added during treatment are generally considered hazardous to the environment, i.e., they "impact" the air and waterways. Thus it is inefficient to add chemicals to treat sewage in order to comply with governmental environmental regulations. Moreover, chemically treating sewage sometimes resulting a failure to safely neutralize the effluent. The usual response is to increase the relative proportions of chemicals added. The sewage plants consequently use more chemicals of which some proportion leaks to the environment. And as sewage production increases because of increased housing or commercial development, still more chemicals are used to meet the growth.
The baseline problem is that these chemicals are expensive. The named-inventor hereof has information and belief that a sewage treatment plant in Harrisburg, Pa. incurs a $360 thousand dollar annual expense for the chemicals it uses.
Another shortcoming associated with the popularly-known sewage treatment plants is their reliance on leach "fields", i.e., shallow ponds or lagoons. The relatively larger sewage treatment plants can be found with several hundreds of the surrounding acres converted into leach fields in which the effluent of the plant is percolated as a step in the treatment to disintegrate/eliminate hazardous components of the effluent, some of which hazardous components were generated by the chemical treating method.
It would be a desirable improvement in sewage handling, if the addition of chemicals could be eliminated. It would also be a desirable improvement in sewage handling if the leach fields could likewise be eliminated. What is needed is a method of processing sewage which eliminates chemical treating and leach fields, and otherwise overcomes the shortcomings of the prior art.